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Fulltext Current Progress in Tendon and Ligament Tissue Engineering

Lim WL, Liau LL, Ng MH, Chowdhury SR, Law JX

Tissue Eng Regen Med, 2019 Dec;16(6):549-571.
PMID: 31824819 DOI: 10.1007/s13770-019-00196-w

BACKGROUND: Tendon and ligament injuries accounted for 30% of all musculoskeletal consultations with 4 million new incidences worldwide each year and thus imposed a significant burden to the society and the economy. Damaged tendon and ligament can severely affect the normal body movement and might lead to many complications if not treated promptly and adequately. Current conventional treatment through surgical repair and tissue graft are ineffective with a high rate of recurrence.
METHODS: In this review, we first discussed the anatomy, physiology and pathophysiology of tendon and ligament injuries and its current treatment. Secondly, we explored the current role of tendon and ligament tissue engineering, describing its recent advances. After that, we also described stem cell and cell secreted product approaches in tendon and ligament injuries. Lastly, we examined the role of the bioreactor and mechanical loading in in vitro maturation of engineered tendon and ligament.
RESULTS: Tissue engineering offers various alternative ways of treatment from biological tissue constructs to stem cell therapy and cell secreted products. Bioreactor with mechanical stimulation is instrumental in preparing mature engineered tendon and ligament substitutes in vitro.
CONCLUSIONS: Tissue engineering showed great promise in replacing the damaged tendon and ligament. However, more study is needed to develop ideal engineered tendon and ligament.
Quality management overview for the production of a tissue-engineered human skin substitute in Malaysia

Seet WT, Mat Afandi MA, Ishak MF, Hassan MNF, Ahmat N, Ng MH, et al.

Stem Cell Res Ther, 2023 Oct 20;14(1):298.
PMID: 37858277 DOI: 10.1186/s13287-023-03536-9

Treatments for skin injuries have recently advanced tremendously. Such treatments include allogeneic and xenogeneic transplants and skin substitutes such as tissue-engineered skin, cultured cells, and stem cells. The aim of this paper is to discuss the general overview of the quality assurance and quality control implemented in the manufacturing of cell and tissue product, with emphasis on our experience in the manufacturing of MyDerm®, an autologous bilayered human skin substitute. Manufacturing MyDerm® requires multiple high-risk open manipulation steps, such as tissue processing, cell culture expansion, and skin construct formation. To ensure the safety and efficacy of this product, the good manufacturing practice (GMP) facility should establish a well-designed quality assurance and quality control (QA/QC) programme. Standard operating procedures (SOP) should be implemented to ensure that the manufacturing process is consistent and performed in a controlled manner. All starting materials, including tissue samples, culture media, reagents, and consumables must be verified and tested to confirm their safety, potency, and sterility. The final products should also undergo a QC testing series to guarantee product safety, efficacy, and overall quality. The aseptic techniques of cleanroom operators and the environmental conditions of the facility are also important, as they directly influence the manufacturing of good-quality products. Hence, personnel training and environmental monitoring are necessary to maintain GMP compliance. Furthermore, risk management implementation is another important aspect of QA/QC, as it is used to identify and determine the risk level and to perform risk assessments when necessary. Moreover, procedures for non-conformance reporting should be established to identify, investigate, and correct deviations that occur during manufacturing. This paper provides insight and an overview of the QA/QC aspect during MyDerm® manufacturing in a GMP-compliant facility in the Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia.
Fulltext The Role and Mechanism of MicroRNA 21 in Osteogenesis: An Update

Subramaniam R, Vijakumaran U, Shanmuganantha L, Law JX, Alias E, Ng MH

Int J Mol Sci, 2023 Jul 11;24(14).
PMID: 37511090 DOI: 10.3390/ijms241411330

MicroRNAs are short, single-stranded ribonucleic acids expressed endogenously in the body to regulate gene expression at the post-translational level, with exogenous microRNA offering an attractive approach to therapy. Among the myriad microRNA candidates involved in controlling bone homeostasis and remodeling, microRNA 21 (miR21) is the most abundant. This paper discusses the studies conducted on the role and mechanism of human miR21 (hsa-miR21) in the regulation of bones and the various pathways mediated by miR21, and explores the feasibility of employing exogenous miR21 as a strategy for promoting osteogenesis. From the literature review, it was clear that miR21 plays a dual role in bone metabolism by regulating both bone formation and bone resorption. There is substantial evidence to date from both in vitro and in vivo studies that exogenous miR21 can successfully accelerate new bone synthesis in the context of bone loss due to injury or osteoporosis. This supports the exploration of applications of exogenous miR21 in bone regenerative therapy in the future.
Age and gender effect on the growth of bone marrow stromal cells in vitro

Shamsul BS, Aminuddin BS, Ng MH, Ruszymah BH

Med J Malaysia, 2004 May;59 Suppl B:196-7.
PMID: 15468885

Bone marrow harvested by aspiration contains connective tissue progenitor cells which can be selectively isolated and induced to express bone phenotype in vitro. The osteoblastic progenitor can be estimated by counting the number of cells attach using the haemacytometer. This study was undertaken to test the hypothesis that human aging is associated with a significant change on the number of osteoblastic progenitors in the bone marrow. Bone marrow aspirates were harvested from 38 patients, 14 men (age 11-70) and 24 women (age 10-70) and cultured in F12: DMEM (1:1). In total 15 bone marrow samples have been isolated from patients above 40 years old (men/women) of age. Fourteen (93.3%) of this samples failed to proliferate. Only one (6.7%) bone marrow sample from a male patient, aged 59 years old was successfully cultured. Seventy percent (16/23) of the samples from patient below than 40 years old were successfully cultured. However, our observation on the survival rate for cells of different gender from patient below 40 years old does not indicate any significant difference. From this study, we conclude that the growth of bone marrow stromal cells possibly for bone engineering is better from bone marrow aspirates of younger patient.
Fulltext Super, red palm and palm oleins improve the blood pressure, heart size, aortic media thickness and lipid profile in spontaneously hypertensive rats

Boon CM, Ng MH, Choo YM, Mok SL

PLoS One, 2013;8(2):e55908.
PMID: 23409085 DOI: 10.1371/journal.pone.0055908

Oleic acid has been shown to lower high blood pressure and provide cardiovascular protection. Curiosity arises as to whether super olein (SO), red palm olein (RPO) and palm olein (PO), which have high oleic acid content, are able to prevent the development of hypertension.
Ultrasound-assisted water-in-palm oil nano-emulsion: Influence of polyglycerol polyricinoleate and NaCl on its stability

Raviadaran R, Ng MH, Manickam S, Chandran D

Ultrason Sonochem, 2019 Apr;52:353-363.
PMID: 30555038 DOI: 10.1016/j.ultsonch.2018.12.012

This study aimed to formulate a stable palm oil-based water-in-oil (W/O) nano-emulsion. Emphasis was placed on the effects of polyglycerol polyricinoleate (PGPR), medium chain triglyceride (MCT), lecithin and sodium chloride (NaCl) addition towards the stability of nano-emulsion. Among the performed analyses were mean droplet diameter (MDD), dispersity index (DI), critical micelle concentration (CMC), lipid peroxidation, viscosity, sedimentation index (SI) and surface morphology. The most stable optimized palm oil-based W/O nano-emulsion was produced using 61.25 wt% of palm oil, 26.25 wt% of MCT, 2.5 wt% of PGPR and 10 wt% of water (0.5 M of NaCl). The MDD and DI of the obtained W/O nano-emulsion were 143.1 ± 8.8 and 0.131 ± 0.094, respectively. After 2 weeks, no sedimentation was observed in W/O nano-emulsion with MDD and DI were 151.2 ± 6.5 nm and 0.156 ± 0.025 respectively. This study clearly found that polyricinoleate non-polar fatty acids of PGPR bound to non-polar fatty acids of palm oil through van der Waals intermolecular forces. While, polyglycerol polar head of PGPR interacts with water molecules through hydrogen bonding, as well as by the bound glyceride units of palm oil. The addition of NaCl further reduced MDD by 70 nm and improved the stability of nano-emulsion through electrostatic and steric repulsions attributed to the dissociation of Na+ and Cl- ions. This study aids to widen the knowledge and interest on the utilization of palm oil for the generation of W/O nano-emulsion, as well as to better understand the interaction between palm oil and PGPR/NaCl in producing nano-emulsion.
pS2 expression in infiltrating ductal carcinoma of the breast correlates with oestrogen receptor positivity but not with histological grade and lymph node status

Looi LM, Azura WW, Cheah PL, Ng MH

Pathology, 2001 Aug;33(3):283-6.
PMID: 11523925

This investigation was carried out to gain insight into the prevalence of pS2 expression in invasive ductal breast carcinoma in the Malaysian population and its correlation with oestrogen receptor (ER) protein expression and tumour aggressiveness. Seventy consecutive infiltrating ductal breast carcinomas treated with mastectomy and axillary lymph node clearance were investigated, using the standard avidin-biotin complex immunoperoxidase method with microwave antigen retrieval and commercial monoclonal antibodies (Dako), for expression of pS2 and human ER. This was correlated against histological grade (modified Bloom and Richardson) and the presence of axillary lymph node metastasis of these carcinomas. Four (5.7%) were grade 1, 40 (57.1%) grade 2 and 26 (37.1%) grade 3 tumours. A total of 45 (64%) showed histological evidence of axillary lymph node metastasis. Forty (57%) were ER-positive, while 31 (44%) were pS2-positive. There was a statistically significant correlation between pS2 and ER expressions (chi2-test with Yates correction: P<0.005). There was no correlation between pS2 expression and histological grade (P>0.1) and the presence of lymph node metastasis (P>0.1). Our findings support the views that pS2 may be a co-marker of endocrine responsiveness in invasive breast cancer and that it does not influence breast cancer biology in terms of potential for metastatic spread.
Fulltext Physicochemical Properties and Biocompatibility of Electrospun Polycaprolactone/Gelatin Nanofibers

Lim WL, Chowdhury SR, Ng MH, Law JX

Int J Environ Res Public Health, 2021 04 29;18(9).
PMID: 33947053 DOI: 10.3390/ijerph18094764

Tissue-engineered substitutes have shown great promise as a potential replacement for current tissue grafts to treat tendon/ligament injury. Herein, we have fabricated aligned polycaprolactone (PCL) and gelatin (GT) nanofibers and further evaluated their physicochemical properties and biocompatibility. PCL and GT were mixed at a ratio of 100:0, 70:30, 50:50, 30:70, 0:100, and electrospun to generate aligned nanofibers. The PCL/GT nanofibers were assessed to determine the diameter, alignment, water contact angle, degradation, and surface chemical analysis. The effects on cells were evaluated through Wharton's jelly-derived mesenchymal stem cell (WJ-MSC) viability, alignment and tenogenic differentiation. The PCL/GT nanofibers were aligned and had a mean fiber diameter within 200-800 nm. Increasing the GT concentration reduced the water contact angle of the nanofibers. GT nanofibers alone degraded fastest, observed only within 2 days. Chemical composition analysis confirmed the presence of PCL and GT in the nanofibers. The WJ-MSCs were aligned and remained viable after 7 days with the PCL/GT nanofibers. Additionally, the PCL/GT nanofibers supported tenogenic differentiation of WJ-MSCs. The fabricated PCL/GT nanofibers have a diameter that closely resembles the native tissue's collagen fibrils and have good biocompatibility. Thus, our study demonstrated the suitability of PCL/GT nanofibers for tendon/ligament tissue engineering applications.
Characteristics and clinical applications of Wharton's jelly-derived mesenchymal stromal cells

Liau LL, Ruszymah BHI, Ng MH, Law JX

Curr Res Transl Med, 2020 01;68(1):5-16.
PMID: 31543433 DOI: 10.1016/j.retram.2019.09.001

Mesenchymal stromal cells (MSCs) are widely used in the clinic because they involve fewer ethical issues and safety concerns compared to other stem cells such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). MSCs derived from umbilical cord Wharton's jelly (WJ-MSCs) have excellent proliferative potential and a faster growth rate and can retain their multipotency for more passages in vitro compared to adult MSCs from bone marrow or adipose tissue. WJ-MSCs are used clinically for repairing tissue injuries of the spinal cord, liver and heart with the aim of regenerating tissue. On the other hand, WJ-MSCs are also used clinically to ameliorate immune-mediated diseases based on their ability to modulate immune responses. In the field of tissue engineering, WJ-MSCs capable of differentiating into multiple cell lineages have been used to produce a variety of engineered tissues in vitro that can then be transplanted in vivo. This review discusses the characteristics of WJ-MSCs, the differences between WJ-MSCs and adult MSCs, clinical studies involving WJ-MSCs and future perspectives of WJ-MSC research and clinical applications. To summarize, WJ-MSCs have shown promise in treating a variety of diseases clinically. However, most clinical trials/studies reported thus far are relatively smaller in scale. The collected evidence is insufficient to support the routine use of WJ-MSC therapy in the clinic. Thus, rigorous clinical trials are needed in the future to obtain more information on WJ-MSC therapy safety and efficacy.
Stable W/O/W multiple nanoemulsion encapsulating natural tocotrienols and caffeic acid with cisplatin synergistically treated cancer cell lines (A549 and HEP G2) and reduced toxicity on normal cell line (HEK 293)

Raviadaran R, Ng MH, Chandran D, Ooi KK, Manickam S

Mater Sci Eng C Mater Biol Appl, 2021 Feb;121:111808.
PMID: 33579452 DOI: 10.1016/j.msec.2020.111808

This work aimed to evaluate the effects of encapsulated tocotrienols (TRF) and caffeic acid (CA) in water-in-oil-in-water (W/O/W) multiple nanoemulsion with cisplatin towards cancer cells. This work is important considering the limited efficacy of cisplatin due to tumour resistance, as well as its severe side effects. A549 and HEP G2 cancer cell lines were utilised for evaluating the efficacy of the encapsulated W/O/W while HEK 293 normal cell line was used for evaluating the toxicity. TRF, CA and CIS synergistically improved apoptosis in the late apoptotic phase in A549 and HEP G2 by 23.1% and 24.9%, respectively. The generation of ROS was enhanced using TRF:CA:CIS by 16.9% and 30.2% for A549 and HEP G2, respectively. Cell cycle analysis showed an enhanced cell arrest in the G0/G1 phase for both A549 and HEP G2. TRF, CA and CIS led to cell death in A549 and HEP G2. For HEK 293, ~33% cell viability was found when only CIS was used while >95% cell viability was observed when TRF, CA and CIS were used. This study demonstrates that the encapsulated TRF and CA in W/O/W with CIS synergistically improved therapeutic efficacy towards cancer cells, as well as lowered the toxicity effects towards normal cells.
Telomerase activation and human papillomavirus infection in invasive uterine cervical carcinoma in a set of Malaysian patients

Cheah PL, Looi LM, Ng MH, Sivanesaratnam V

J Clin Pathol, 2002 Jan;55(1):22-6.
PMID: 11825919

AIM: Telomerase activity was studied in invasive uterine cervical carcinoma to assess whether it was activated during cervical malignant transformation and to look for a possible association with human papillomavirus (HPV) infection in a set of Malaysian patients.
METHODS: Histologically confirmed invasive cervical carcinoma and benign cervices were assayed for telomerase activity using a commercial telomerase polymerase chain reaction (PCR) enzyme linked immunosorbent assay kit. The same cases were subjected to PCR detection of HPV using type specific (HPV types 6b, 11, 16, and 18) followed by L1 open reading frame (ORF) consensus primers.
RESULTS: HPV was detected in 18 (13 HPV-16, one HPV-6b, four only L1 ORF) of 20 invasive cervical carcinoma and one (only L1 ORF) of 19 benign cervices. Raised telomerase activity (A(450 nm) > 0.215) was detected in 11 cervical carcinomas, with A(450 nm) ranging between 0.238 and 21.790 (mean, 3.952) in positive squamous carcinomas, whereas A(450 nm) was only 0.222 in the one positive adenosquamous carcinoma. Five of 11 cervical carcinomas in stage I, three of six in stage II, both in stage III, and the only case in stage IV showed telomerase activation. Increased telomerase activity was noted in five of the 12 lymph node negative, five of the seven lymph node status unknown cases, and the one case with presumed lymph node metastasis. Ten of 18 HPV positive and one of two HPV negative cervical carcinomas showed telomerase upregulation.
CONCLUSIONS: Telomerase is activated in invasive cervical carcinoma. Although larger studies are needed, there seems to be no clear association between telomerase upregulation and HPV status, although there is a suggestion of increased telomerase activity in squamous carcinomas and late stage disease.
Ultrasound-assisted production of palm oil-based isotonic W/O/W multiple nanoemulsion encapsulating both hydrophobic tocotrienols and hydrophilic caffeic acid with enhanced stability using oil-based Sucragel

Raviadaran R, Ng MH, Manickam S, Chandran D

Ultrason Sonochem, 2020 Jun;64:104995.
PMID: 32106064 DOI: 10.1016/j.ultsonch.2020.104995

In this work, the effects of thickeners and tonicity towards producing stable palm oil-based water-in-oil-in-water (W/O/W) multiple nanoemulsion using ultrasound and microfluidizer were investigated. Palm oil, Sucragel, polyglycerol polyricinoleate, Tween 80, Xanthan gum, and NaCl were used. W/O/W was formed under the optimized conditions of ultrasound at 40% amplitude and for 180 s of irradiation time, whereas for the microfluidizer, the optimized conditions were 350 bar and 8 cycles. This is the first work that successfully utilized Sucragel (oil-based thickener) in imparting enhanced stability in W/O/W. W/O/W with isotonic stabilization produced the lowest change in the mean droplet diameter (MDD), NaCl concentration, and water content by 1.5%, 2.6%, and 0.4%, respectively, due to reduced water movement. The final optimized W/O/W possessed MDD and dispersity index of 175.5 ± 9.8 and 0.232 ± 0.012, respectively. The future direction of formulating stable W/O/W would be by employing oil phase thickeners and isotonicity. The observed ~12 times lesser energy consumed by ultrasound than microfluidizer to generate a comparable droplet size of ~235 nm, further confirms its potential in generating the droplets energy-efficiently.
Mesenchymal Stem Cell Transplantation for the Treatment of Age-Related Musculoskeletal Frailty

Mahindran E, Law JX, Ng MH, Nordin F

Int J Mol Sci, 2021 Sep 29;22(19).
PMID: 34638883 DOI: 10.3390/ijms221910542

Projected life expectancy continues to grow worldwide owing to the advancement of new treatments and technologies leading to rapid growth of geriatric population. Thus, age-associated diseases especially in the musculoskeletal system are becoming more common. Loss of bone (osteoporosis) and muscle (sarcopenia) mass are conditions whose prevalence is increasing because of the change in population distribution in the world towards an older mean age. The deterioration in the bone and muscle functions can cause severe disability and seriously affects the patients' quality of life. Currently, there is no treatment to prevent and reverse age-related musculoskeletal frailty. Existing interventions are mainly to slow down and control the signs and symptoms. Mesenchymal stem cell (MSC) transplantation is a promising approach to attenuate age-related musculoskeletal frailty. This review compiles the present knowledge of the causes and changes of the musculoskeletal frailty and the potential of MSC transplantation as a regenerative therapy for age-related musculoskeletal frailty.
Fulltext Potential of Mesenchymal Stem Cells in the Rejuvenation of the Aging Immune System

Yeo GEC, Ng MH, Nordin FB, Law JX

Int J Mol Sci, 2021 May 27;22(11).
PMID: 34072224 DOI: 10.3390/ijms22115749

Rapid growth of the geriatric population has been made possible with advancements in pharmaceutical and health sciences. Hence, age-associated diseases are becoming more common. Aging encompasses deterioration of the immune system, known as immunosenescence. Dysregulation of the immune cell production, differentiation, and functioning lead to a chronic subclinical inflammatory state termed inflammaging. The hallmarks of the aging immune system are decreased naïve cells, increased memory cells, and increased serum levels of pro-inflammatory cytokines. Mesenchymal stem cell (MSC) transplantation is a promising solution to halt immunosenescence as the cells have excellent immunomodulatory functions and low immunogenicity. This review compiles the present knowledge of the causes and changes of the aging immune system and the potential of MSC transplantation as a regenerative therapy for immunosenescence.
Fulltext Unseen Weapons: Bacterial Extracellular Vesicles and the Spread of Antibiotic Resistance in Aquatic Environments

Barathan M, Ng SL, Lokanathan Y, Ng MH, Law JX

Int J Mol Sci, 2024 Mar 07;25(6).
PMID: 38542054 DOI: 10.3390/ijms25063080

This paper sheds light on the alarming issue of antibiotic resistance (ABR) in aquatic environments, exploring its detrimental effects on ecosystems and public health. It examines the multifaceted role of antibiotic use in aquaculture, agricultural runoff, and industrial waste in fostering the development and dissemination of resistant bacteria. The intricate interplay between various environmental factors, horizontal gene transfer, and bacterial extracellular vesicles (BEVs) in accelerating the spread of ABR is comprehensively discussed. Various BEVs carrying resistance genes like blaCTX-M, tetA, floR, and sul/I, as well as their contribution to the dominance of multidrug-resistant bacteria, are highlighted. The potential of BEVs as both a threat and a tool in combating ABR is explored, with promising strategies like targeted antimicrobial delivery systems and probiotic-derived EVs holding significant promise. This paper underscores the urgency of understanding the intricate interplay between BEVs and ABR in aquatic environments. By unraveling these unseen weapons, we pave the way for developing effective strategies to mitigate the spread of ABR, advocating for a multidisciplinary approach that includes stringent regulations, enhanced wastewater treatment, and the adoption of sustainable practices in aquaculture.
Fulltext The Profound Influence of Gut Microbiome and Extracellular Vesicles on Animal Health and Disease

Barathan M, Ng SL, Lokanathan Y, Ng MH, Law JX

Int J Mol Sci, 2024 Apr 04;25(7).
PMID: 38612834 DOI: 10.3390/ijms25074024

The animal gut microbiota, comprising a diverse array of microorganisms, plays a pivotal role in shaping host health and physiology. This review explores the intricate dynamics of the gut microbiome in animals, focusing on its composition, function, and impact on host-microbe interactions. The composition of the intestinal microbiota in animals is influenced by the host ecology, including factors such as temperature, pH, oxygen levels, and nutrient availability, as well as genetic makeup, diet, habitat, stressors, and husbandry practices. Dysbiosis can lead to various gastrointestinal and immune-related issues in animals, impacting overall health and productivity. Extracellular vesicles (EVs), particularly exosomes derived from gut microbiota, play a crucial role in intercellular communication, influencing host health by transporting bioactive molecules across barriers like the intestinal and brain barriers. Dysregulation of the gut-brain axis has implications for various disorders in animals, highlighting the potential role of microbiota-derived EVs in disease progression. Therapeutic approaches to modulate gut microbiota, such as probiotics, prebiotics, microbial transplants, and phage therapy, offer promising strategies for enhancing animal health and performance. Studies investigating the effects of phage therapy on gut microbiota composition have shown promising results, with potential implications for improving animal health and food safety in poultry production systems. Understanding the complex interactions between host ecology, gut microbiota, and EVs provides valuable insights into the mechanisms underlying host-microbe interactions and their impact on animal health and productivity. Further research in this field is essential for developing effective therapeutic interventions and management strategies to promote gut health and overall well-being in animals.
Fulltext Telomerase activation in neoplastic cell immortalization and tumour progression

Looi LM, Ng MH, Cheah PL

Malays J Pathol, 2007 Jun;29(1):33-5.
PMID: 19105326 MyJurnal

The unique ability of tumour cells to proliferate indefinitely is crucial to neoplastic progression as it allows these cells to express the aggressive properties of cancer without the censure of physiological ageing. This is in contrast to normal somatic cells which are subject to a "mitotic clock," a phenomenon that has been linked to telomeric shortening after each round of cell replication, so that eventually the loss of genetic material reaches a critical stage and the cells undergo senescence and cell death. A study was conducted to investigate the role of telomerase, an RNA-containing enzyme that restores the telomere length, in the neoplastic cell immortalization and progression process. Fresh human tissue samples taken from excision specimens received by the Department of Pathology, University of Malaya Medical Centre, were investigated for telomerase activity using a commercial Telomerase PCR-ELISA kit (Boehringer Mannheim). Specimens comprised 33 breast lesions (10 infiltrating breast adenocarcinoma, 13 fibroadenoma and 10 non-neoplastic breast tissue), 27 colonic lesions (17 colonic adenocarcinoma and 10 non-neoplastic colonic mucosa) and 42 cervical lesions (20 cervical carcinoma and 22 non-neoplastic cervical tissues). Telomerase activity was found in 6 (60%) of 10 breast carcinomas, 6 (46%) of 13 fibroadenomas, none of the 10 nonneoplastic breast samples, 3 (17.6%) of 17 colon carcinomas and none of the 10 non-neoplastic colonic mucosal samples, 12 (60%) of 20 cervical carcinoma and 3 (13.6%) of 22 non-neoplastic cervical samples. 5/10 (50%) Stage I, 4/7 (57%) Stage II, 2/2 (100%) Stage III and 1/1 (100%) Stage IV cervical carcinomas showed telomerase activity. These findings support a contributory role for telomerase in tumourigenesis with activation occurring from neoplastic transformation and increasing with tumour progression.
Recycling of deep eutectic solvent in the extraction of ferulic acid from oil palm empty fruit bunch

Ng MH, Nu'man AH, Hasliyanti A

J Sep Sci, 2024 Feb;47(4):e2300842.
PMID: 38403445 DOI: 10.1002/jssc.202300842

The study explored ferulic acid extraction from palm empty fruit bunch (EFB) fiber using deep eutectic solvent (DES) of chlorine chloride-acetic acid as the extraction medium and the way to recover and recycle the DES thereafter. Antisolvent was added to selectively precipitate the ferulic acid, which was recovered by filtration thereafter. Recycling the DES without further purification led to increased ferulic acid yield with each subsequent extraction, likely due to retained ferulic acid. The retained ferulic acid and other impurities could be removed by precipitation brought upon by the addition of a second antisolvent. 1H nuclear magnetic resonance revealed that there was no excess ferulic acid in the recycled DES-treated with two types of antisolvents (ethanol and water). The yield of ferulic acid increased from 0.1367-0.1856 g/g when treated with only one antisolvent to 0.1368-0.2897 g/g with two antisolvent treatments. Oil droplets were also observed in the DES upon the addition of antisolvent 2, with recovered oil ranging from 0.6% to 3%. The study emphasized the significance of using DES as an extraction medium for ferulic acid from oil palm EFB fiber and the method to recycle the DES for subsequent processes.
Fulltext Improved Method for the Qualitative Analyses of Palm Oil Carotenes Using UPLC

Ng MH, Choo YM

J Chromatogr Sci, 2016 Apr;54(4):633-8.
PMID: 26941414 DOI: 10.1093/chromsci/bmv241

Palm oil is the richest source of natural carotenes, comprising 500-700 ppm in crude palm oil (CPO). Its concentration is found to be much higher in oil extracted from palm-pressed fiber, a by-product from the milling of oil palm fruits. There are 11 types of carotenes in palm oil, excluding the cis/trans isomers of some of the carotenes. Qualitative separation of these individual carotenes is particularly useful for the identification and confirmation of different types of oil as the carotenes profile is unique to each type of vegetable oil. Previous studies on HPLC separation of the individual palm carotenes reported a total analyses time of up to 100 min using C30 stationary phase. In this study, the separation was completed in <5 min. The qualitative separation was successfully carried out using a commonly used stationary phase, C18.
Applications of packed and capillary supercritical fluid chromatography in the separation of tocochromanols

Ng MH, Din AK

J Sep Sci, 2020 Jan;43(1):285-291.
PMID: 31294513 DOI: 10.1002/jssc.201900342

Tocochromanols consisting of tocopherols and tocotrienols, is collectively known as vitamin E. Similarity in their structures, physical and chemical properties rendered the tocochromanols to be subject of chromatography interest. Supercritical fluid chromatography is a highly efficient tool for the separation and analysis of tocochromanols. Separation and analysis of tocochromanols using supercritical fluid chromatography had been carried out in the past using capillary or packed columns. Each of these techniques offer their own advantages and drawbacks. Besides being used for analysis, packed column supercritical fluid chromatography found applications as a purification and content enrichment tool. Emergence of new equipment and stationary phase technologies in recent years also helped in making supercritical fluid chromatography a highly efficient tool for the separation and analysis of tocochromanols. This paper gives an insight into the use of capillary and packed columns in supercritical fluid chromatography for the separation and/or analysis of tocochromanols. The types of stationary phase used, as well as chromatographic conditions are also discussed.

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